Semiconductor packages provide environmental protection to integrated circuit chips enclosed within the package. Semiconductor packages include a supporting leadframe, one or more chips attached to the leadframe, encapsulating material molded over the leadframe and the chip(s), and multiple leads configured to electrically connect the chip to the “outside” world.
The leadframe supports the chip, and the encapsulation material shelters the chip(s) from the environment. During use, the chip can increase in temperature. The increase in temperature during use, and the subsequent cooling of the chip when not in use, causes thermal cycling of the chip and the package. In general, the chip, the leadframe, and the encapsulation material each have a different coefficient of thermal expansion (CTE). The differing CTE for the components of the package has the potential to delaminate the leadframe from the encapsulation material during thermal cycling. Delaminated leadframes potentially interrupt the electrical connection to the chip and between the chip and the outside world, which is undesirable for both the package manufacturer and the end-user of the package.
For these and other reasons there is a need for the present invention.